Bees in Urban Agriculture
Pollination is an absolutely critical event for the success of urban farms, and only a few species are capable of facilitating this process. Bees are the most well-known and important pollinator in North America, and their role in urban agriculture cannot be ignored. Policies regarding bees in an urban setting can be difficult due to general distaste for bees, fear of stinging, and the threat of allergic reactions by certain members of the public4. Despite these potential setbacks, urban settings can be perfect for bees in many ways. Urban hives are known to be more productive than rural hives because cities are home to countless plant species from all over the world, allowing the bees to diversify and produce honey at a higher rate1. Furthermore, summers in the Northern United States provide an incredible availability of resources, especially in an area densely occupied by home gardens or urban farms. These areas also are accompanied by a reduced risk of pesticide exposure compared to rural areas, where most farmers spray entire fields of crops with pesticides that can be devastating for a hive of honey bees4. For these reasons, the use of honey bees to both produce honey and pollinate gardens and farms in urban areas is a potentially valuable endeavor. While much can be made of the potential increase in the occurrence of bee stings, this issue is believed to be minimal if hives are properly located. Honey bees stay where the hive is placed, only venturing within a two-mile radius in search of food and water. When bees are away from the hive, they are exclusively in search of honey and will attempt to avoid stinging another animal at all costs4. To avoid stinging, people must simply avoid getting too close to the hive without the proper protection. Bees fly thirty feet into the air from the hive and then go in search of honey, so as long as they are not disturbed before reaching this altitude, there will likely be no problems. If the hive is interfered with when the bees are coming or going, however, they will certainly attack. Proper precautions should be taken in urban areas to ensure that unaware individuals or children cannot accidentally encounter the hive. Pollination The role of pollination in agricultural endeavors, whether urban or rural, cannot be understated. In the year 2000, pollination was worth an estimated $14.6 billion in the United States agriculture industry3. If flowers are not pollinated, they fail to produce seeds or fruits, ruining the yield of many important food crops such as tomatoes, cucumbers, pumpkins, peppers, and squash among others3. As urban farms become more popular, urban pollinators will be needed to achieve the desired production. While most rural farms depend on corporate beekeepers who ship beehives around the country to various blooming seasons that occur throughout the year, this may not be a feasible option for many urban farms and gardens. Honey bees are not native to North America, and many individuals in the upper Midwest may prefer the idea of having their crops pollinated by native species. In the city of Vancouver, 55 native species of bees have been observed pollinating various flowers, so in theory this is a potential option2. However, these species are impossible to control, as they do not follow a hive as honey bees do, and there is no guarantee that they will find any particular garden or farm. This is especially problematic given the widespread decline of native bee populations across the United States and the entire world5. If you do wish to attract native pollinators, the best option is to simply provide better habitat by planting more flowering species and hoping they are discovered. For a more focused operation, however, honey bees are a more practical solution, as they will only venture within a two mile radius of the hive and will pollinate essentially all of the available flowering plants in this area4. A honey bee hive can thus be a sensible addition to an urban farming operation. Honey Production Using honey bees for pollination carries the added benefit of honey production. Hives in urban settings in London produce 27,000 kg of honey annually, which is valued at an estimated $26.2 million, as well as $200,000 from beeswax. The average London hive produces 40 pounds of honey per year, a substantial output for a small operation in an urban setting1. Colony Collapse Disorder One major concern for honey bee populations is often referred to as the Colony Collapse Disorder (CCD). CCD describes a phenomenon where colonies experience a dramatic drop in survival during the winter season. Prior to the onset of CCD, 90 percent of bees in any given hive were expected to survive the winter. Now, for commercial beekeepers, expectations have plummeted below 50 percent4. While there is no single culprit for colony collapse disorder, a number of factors including widespread pesticide use, the increase in parasitic Varroa mite populations, viruses, pathogens, and malnutrition as a result of declines in the diversity and abundance of flowers4,6. This can be a major setback for a beekeeping operation, so it is important to reduce the risk factors in your local area and keep in mind that CCD has been found to be contagious from hive to hive, so avoid proximity to hives experiencing this phenomenon. On the positive side, smaller bee operations in urban areas report better survival rates than commercial beekeepers, typically around 75 to 80 percent4. Native pollinators are not subject to CCD specifically, but their populations have experienced similar declines worldwide5. Needs of the Hive When establishing a new hive, habitat should be the biggest consideration, keeping in mind that lack of food is often the biggest problem in an urban setting. The bees will search for food in a two mile radius around the hive, so make sure there are plenty of flowering trees like basswoods or maples, which also provide pollen, as well as other flowering plants4. Bees in Vancouver were found to associate in high numbers with blackberry plants, buttercups, and cotoneasters, as well as with community gardens in general, which bodes well for urban farmers hoping to add honey bees to their inventory2. Wild, unmanaged areas within the city had higher bee diversity than managed lawns or gardens, suggesting that these are optimal for recruiting native pollinator species2. Low bee diversity and abundance was observed near traditional flower gardens containing tulips and petunias, so carefully choose which species of flowers you decide to plant2. In addition to needing flowering plants, pine trees provide sap that the bees use to repair damages to the hive, so having at least a few of these nearby can be important4. The location of the hive in an urban setting is of critical importance. An optimal location can often be on the top of a building, as the bees will fly up to two miles in the air when coming and going from the hive anyway, and this can ensure that very few people will accidentally encounter the hive. High positions are always preferable to low positions. Other important factors for a successful hive include a location that is out of the wind, that receives sunshine from the East in the morning and shade in the afternoon, and a significant source of water within a two mile radius. Other important considerations when establishing a hive are the use of pesticides within a two mile radius by neighbors that may harm the bees. Be sure to talk with your community about your beehive to request that they abstain from using pesticides and calm their fears about being stung. It is believed that every hive needs four of the following five features to survive4: 1. A healthy young queen 2. A disease-free population 3. Minimal mite population 4. Abundant supply of food from flowering plants 5. Location with both minimal wind and morning sun. Protecting the Hive During Winter In the upper Midwest, harsh winters must be taken into consideration for virtually every urban agricultural endeavor. A honey bee hive can survive the winter with no major setbacks provided that the proper precautions are taken. As winter approaches, all surplus honey should be removed from the hive, leaving at least 60 lbs. of honey and pollen to feed the bees during the winter. The hive should then be wrapped with approximately 30 lbs. of black tar paper, leaving an opening in the bottom with a small crack for ventilation. The top should be wrapped around a top-hive feeder, which will allow you to add additional food to help the colony survive during the winter. Honey, sugar water, and corn syrup are each appropriate foods for the hive, and they should be added through the feeder so long as the bees continue eating it. Even after the temperature begins to warm up in the early spring, bees should be fed in this way. At this point in the year, their natural food source, nectar and pollen from flowering plants, is still not available. The biggest risk to the hive during a winter in the upper Midwest is that in extremely cold temperatures the bees form a dense cluster facing inwards toward the queen. Doing so allows them to maintain the hive at a temperature of 92 degrees Fahrenheit. Unfortunately, if the cold temperatures persist for too long, the bees will starve to death rather than abandoning the cluster to eat the provided food. Despite this potential setback, honey bees are kept throughout the year in many cold climates throughout Minnesota4. Citations 1. Garnett, Tara. "Urban agriculture in London: rethinking our food economy."Growing Cities, Growing Food. German Foundation for International Development, Feldafing, Germany (2000): 477-500. 2. Tommasi, Désirée, et al. "Bee diversity and abundance in an urban setting."The Canadian Entomologist 136.06 (2004): 851-869. 3. Morse, Roger A., and Nicholas W. Calderone. "The value of honey bees as pollinators of US crops in 2000." Bee culture 128.3 (2000): 1-15. 4. Treder, Gene. Interview by author. Email correspondence. Rochester, MN, USA. March 8-10, 2014. 5. Potts, Simon G., et al. "Global pollinator declines: trends, impacts and drivers."Trends in ecology & evolution 25.6 (2010): 345-353. 6. Evans, Jay D., et al. "Colony collapse disorder: a descriptive study." ''PloS one''4.8 (2009): e6481.